This document claims priority to French application number 0107309 filed Jun. 5, 2001, the entire content of which is hereby incorporated by reference.
The present invention relates to artificial tanning agents, and particularly to an article for applying artificial tanning agents, and a method for making such an article.
Discussion of Background
Artificial tanning creams can be packaged in pots or tubes and applied to the body or the face using the fingers. However, it is difficult to uniformly apply the cream with this approach, and there is a risk of non-uniform coloring the skin. In addition, the fingers used for spreading the cream can also be marked or discolored. In addition, in order to preserve the tanning agent, the cream contains preservatives that can lead to irritation of the skin.
U.S. Pat. No. 5,972,360 discloses a towelette impregnated with an artificial tanning agent. Such a towelette makes it easier to apply the desired quantity of the agent on the skin, but the user nevertheless runs the risk of discoloring the fingers that come into contact with the towelette. In addition, in order to ensure that the agent is properly conserved, the towelette must be packaged in a bag that is leaktight and opaque, and thus relatively expensive. Since the towelette is not dry, preservatives are also likely to be used.
International patent application No. WO 01/08658 discloses a cleaning cloth that is impregnated with a surfactant. The cloth includes two layers, e.g., constituted by non-woven fabrics. The cloth can also contain an artificial tanning agent placed on one of the layers and then covered by the other layer. One of the layers can be impregnated with the artificial tanning agent, in particular by spraying. However, difficulties can be encountered with the agent impregnating one of the layers throughout its thickness. In addition, the manufacture of such pieces of cloth can be relatively complex.
European patent application No. EP 0 998 903 (which has a pending U.S. counterpart Ser. No. 09/418,825 and which is incorporated herein by reference) discloses a patch comprising both a matrix capable of containing an artificial tanning agent and a permeable support. The artificial tanning agent forms a solution when the matrix is brought into contact with a suitable liquid. The matrix is covered on one face by a removable protective film. Applying an artificial tanning agent by means of a patch stuck to the skin is not always satisfactory, since there is always a risk of the skin being colored in non-uniform manner as a result of the length of time the patch remains stationary on the skin.
There exists a need for a device or article that allows an artificial tanning agent to be easily applied to the skin, while allowing the agent to be conserved properly, and also reducing the risk of the user discoloring the fingers. There is also a need to be able to obtain non-uniform coloring of the treated surface, should that be desired, e.g., in order to decorate it with a design or motif.
The invention provides a novel applicator device and method in which an adhesive matrix is disposed between at least two layers that are permanently bonded to the matrix, with at least one of the layers being permeable to a liquid. The matrix contains at least one artificial tanning agent suitable for acting on the skin when the matrix is put into contact with a liquid, which can be, for example, water or a liquid that includes water and alcohol.
As used herein, two or more structural elements that are xe2x80x9cpermanently bondedxe2x80x9d to each other cannot be readily or easily separated from one another through the use of a completely manually-applied pulling force. For example, a release layer in contact with an adhesive on a bandage would not be xe2x80x9cpermanently bondedxe2x80x9d to the remainder of the bandage.
The term xe2x80x9cartificial tanning agentxe2x80x9d is used in the present invention to encompass compounds which serve themselves to color the skin, i.e. self-tanning or sunless tanning agents such as dihydroxyacetone (DHA) or erytrulose, for example, as well as agents which require exposure to ultraviolet (UV) radiation, i.e., tanning accelerators such as melanin precursors, for example. The artificial tanning agent can optionally be tinted.
The invention enables the artificial tanning agent to be conserved properly without using preservatives since it may be stored in a substantially anhydrous medium within the matrix. Manufacture of the device can also be relatively simple since it is the matrix containing the artificial tanning agent which provides the fastening or adhesion between the layers.
In addition, the article can be made in such a manner as to be non-adhesive or non-stick with respect to the surface to which the tanning agent is to be applied, so as to be easily moved in contact with the skin during application, thus making it possible to obtain color that is uniform. Alternately, where desired, the article can be made to have a certain outline or profile, and the permeable layer facing the skin can be made in such a manner as to allow the matrix, once the device has been impregnated with the liquid, to burst or break-up and pass through the permeable layer. The matrix then causes the outside face of the layer to become permeable to the adhesive, thus enabling it to be held stationary on the skin for a length of time that is sufficient to mark the skin with a desired design or motif by changing the color of the skin. In a variant, or where appropriate, selected portions of the permeable layer can also be made to be impermeable to the artificial tanning agent e.g., by covering the permeable layer with an impermeable web that is perforated in certain locations, or by selectively printing, such as by silkscreen printing, on the permeable layer using a substance that impedes or prevents the artificial tanning agent from diffusing towards the skin. Alternatively selected portions of the layer can be treated in a manner that accelerates (e.g., by a mechanical and/or chemical treatment that increases the porosity or permeability of the substrate) such diffusion so that the tanning agent is better delivered to the areas where a design is desired. The motif made on the skin may be constituted, for example, by a representation of the moon, a star, or any other shape or design.
In one embodiment, the matrix contains one or more compounds soluble in the liquid used in sufficient quantity such that the matrix at least partially loses its cohesion on making contact with the liquid. This arrangement can facilitate delivery of the artificial tanning agent through the permeable layer facing the skin.
In another aspect of an embodiment, the matrix contains a filler of one or more compounds capable of swelling on coming into contact with the liquid in sufficient quantity for the matrix to lose its cohesion on coming into contact with the liquid. As with the above embodiment, this arrangement can facilitate delivery of the artificial tanning agent.
The matrix may also contain one or more moisture absorbing compounds. Where a moisture-absorbing compound is included, the moisture-absorbing compound is preferably 0.2% to 60%, and more preferably 0.5% to 40% by weight of the matrix. By way of example, this compound may be selected from the following list: polyacrylates; silica; cotton fibers; starches; alginates; calcium carbonates; magnesium carbonates; viscose; cellulose; and lyophilisates.
The matrix may also contain a filler of one or more substantially inert compounds, such as a polyamide powder or microbeads, for example, in order to encourage bursting or breaking-up of the matrix on coming into contact with the liquid.
In accordance with the invention, when a liquid (e.g., water or a water and alcohol solution) is applied to the article, it wets the matrix and allows the tanning agent to be delivered to the skin through one or more of the layers that are permeable to the tanning agent. The tanning agent can be delivered by being dissolved by the liquid and/or by being carried as a suspension in the liquid. Depending upon the proportions of the tanning agent with respect to the remainder of the matrix, it can also be desirable to at least partially degrade the remainder of the matrix to increase the proportion of the tanning agent contained within the matrix that can be exposed to the liquid. As discussed above, the degradation of the matrix can be accomplished by including (in addition to the adhesive that holds the substrate layers together and the tanning agent) one or more materials or compounds that are: dissolved by the liquid; absorb the liquid or swell when contacted by the liquid to encourage breaking-up or bursting of the matrix; or a substance that becomes suspended/washed away or otherwise loses its structural integrity when exposed to the liquid to assist in breaking up of the matrix and expose the tanning agent to the liquid. Preferably, the adhesive is present in sufficient quantities such that adhesion of the substrate layers to the matrix (and thus to each other) is maintained after the matrix is contacted with the liquid. Where it is desired to provide a sticky or adhesive surface to the article upon wetting with a liquid (to hold the article temporarily against the skin, e.g., to apply a design or motif to the skin), a second adhesive or filler can be provided in the matrix (i.e., other than the adhesive which holds the layer to the matrix), with the second adhesive or filler activated or dissolved upon contact with the liquid so that it can pass through one of the permeable layers and assist in temporarily holding the article against the skin to apply the design. This second adhesive or filler provides a sticky or tacky temporary adhesion of the article to the skin so that the user can remove the article when desired. The tanning agent could be present within the matrix as a liquid, gel or cream (within pockets or encapsulated portions defined by the matrix) which is released as the matrix is wetted with the liquid and the matrix degrades or partially breaks-up. However, the artificial tanning agent is preferably present in solid, dry form (until use is desired) for ease of manufacture and to minimize the need for preservatives.
In addition to the artificial tanning agent, the matrix can contain one or more active agents selected from the following list: vitamin C; vitamin A; vitamin F; glycerin; laponite; wetting agents; collagen; salicylic acid; do acid; caffeine; essential aromatic oils; coloring agents; anti-oxidants; free radical scavengers; moisturizers; depigmenting agents; liporegulators; antiacne agents; antidandruff agents; anti-aging agents; softeners; antiwrinkle agents; keratolitic agents; anti-inflammatory agents; fresheners; healing agents; vascular protectors; antibacterial agents; antifungal agents; antiperspirants; deodorants; skin conditioners; anesthetics; immunomodulators; nourishing agents; melatonin; and dehydroepiandrosterone (DHEA).
The matrix may also include magnetizable or magnetized particles.
The adhesive matrix may be based on an adhesive that is not soluble in water when in the cross-linked state. Examples of adhesives that can be used in the adhesive matrix include: vinyl-based adhesives; polyvinyl alcohol (PVA)-based adhesives; polyvinyl pyrrolidene (PVP)-based adhesives; pseudolatex-based adhesives; acrylic polymer-based adhesives; polyurethane-based adhesives; and latex elastomer-based adhesives. The adhesive should be selected to be compatible with the artificial tanning agent and the active agent(s) used (if any).
Examples of preferred substrate layers that can be used with the matrix include: a non-woven fabric, preferably an aerated non-woven fabric that optionally can be perforated; a foam; a woven fabric; plastics (that optionally can be perforated), and a metallized film (that can also optionally be perforated). By way of example, a non-woven fabric can be an aerated and perforated so as to enable the matrix, after coming into contact with the liquid, to pass through the perforations in the non-woven fabric and between the fibers away from the perforations, where appropriate, after it has burst, thereby facilitating transfer of the artificial tanning agent to the skin, and possibly conferring adhesive properties to the outside surface of the article.
In one embodiment, the matrix is located between a layer that is permeable and a layer that is impermeable to the liquid. In particular, the matrix can be located between a hydrophilic layer and a layer that is impermeable to the liquid, e.g., between a hydrophilic non-woven fabric and an impermeable plastic film. The leakproof plastic film may itself be covered in a non-woven fabric or in flocking. The presence of an impermeable layer is useful for isolating the user""s fingers from the matrix at the time of use, thus enabling the user to avoid marking or discoloration of the fingers.
In another particular embodiment, the matrix is located between two layers that are permeable to the liquid. In particular, the matrix can be located between two hydrophilic layers or between a hydrophilic layer and a hydrophobic layer. The matrix may thus be placed between a woven fabric or a non-woven fabric that is hydrophilic and a woven fabric or a non-woven fabric that is hydrophobic. In one example, the matrix can be placed between a perforated plastic film and a hydrophilic nonwoven fabric. The use of a hydrophobic non-woven fabric makes it possible to obtain poor wetting of one surface of the device or article, which is the surface held in the hand, while nevertheless ensuring that the surface is more pleasing to touch than it would be if constituted solely by a leakproof plastic film.
By way of example, the device can be in the form of a disk, as a piece of cloth (having a rectangular, square, or various other shapes), or a glove. When it is in the form of a glove, it preferably includes a layer that is impermeable to the liquid used, with the impermeable layer disposed between the matrix and the inside of the glove.
In accordance with the invention, the layers between which the matrix is located may be free from any artificial tanning agent on their surfaces remote from the matrix (the outer surfaces of the article) until the matrix is contacted with the liquid. This ensures that the artificial tanning agent is relatively well protected from UV radiation, particularly when the layers outside the matrix are adapted to provide a UV radiation barrier. There is therefore no need to provide for individual opaque packaging, and this reduces the cost of the article quite considerably.
Another advantageous aspect of the invention provides a box containing a plurality of articles such as disks, pieces of cloth, or gloves in accordance with the invention.
A further advantageous aspect of the invention provides a kit that includes a device or article as described above together with a receptacle containing the liquid. The liquid can be, for example, water, or a liquid that includes water an alcohol such as a water and alcohol lotion, and optionally contains one or more active agents suitable for encouraging penetration of the artificial tanning agent into the skin.
The article may also be in the form of a roll, optionally with perforations making it easier to tear into smaller sized articles or sheets.
According to an advantageous method for manufacturing the article of the invention, an artificial tanning agent is incorporated in an adhesive-based matrix. The matrix is placed between at least two layers, at least one of which is permeable to a liquid, with the liquid enabling the artificial tanning agent to act on the skin when the matrix is put into contact therewith. The matrix need not be in an aqueous phase during manufacture and/or storage of the article, thus making it possible to avoid using preservatives.
In one example of the method, the matrix is assembled with one of the layers without impregnating it completely through, with the impregnation preferably extending to no more than 25% of its thickness, for example. The other layer, e.g., the layer which is more permeable to the liquid used and through which the artificial tanning agent is released to the skin, may be fixed on the matrix merely by adhesive contact. Prior to contacting the liquid, the matrix is thus kept away from the outside surfaces of the article, thereby enabling the matrix to be protected, in particular from UV radiation.